坛紫菜应答高温胁迫的信号转导网络解析

Pyropia haitanensis is an economically important marine crop in China. A major problem in Pyropia farming is thallus decay in response to high temperature stress. Molecular mechanism studies of temperature stress can help to resolve the issue of thallus decay. In this study, in order to clarify the signal transduction mechanism of P.haitanensis in response to high temperature stress, the technology of phosphoproteomics will be used to analyze the change of expression patterns and phosphorylation locus of proteins in a high-temperature tolerant line of P.haitanensis when cultured under both high-temperature stress and normal temperatures. Based on the comparative phosphoproteomics study, we will construct phosphoproteomics profiles of the entire set of proteins. Then, all the phosphoproteomics data will be collated with transcriptome data to select specific phosphorylation locus related to the differentially expressed genes in response to high temperature stress. Based on these studies, signal transduction network of P.haitanensis in response to high-temperature stress will be constructed. We will also analyze the relations of specific phosphorylation locus and high temperature tolerance of P.haitanensis. Additionally,, all the results will be integrated with transcriptome data and proteome data to further analyze the mechanisms of high-temperature tolerance in P. haitanensis. The transcriptome data and proteome data have been obtained from the same line of P. haitanensis, cultured under both high-temperature stress and normal temperatures. These results will create a foundation for a breeding profile for P. haitanensis in relation to stress tolerance.

坛紫菜应答高温胁迫信号转导机制的阐明是全面解析坛紫菜高温胁迫应答机制的关键。本研究根据高温胁迫应答的“信号感受—转导—蛋白磷酸化修饰—转录调控—基因差异表达—基因功能分析”的基本过程和研究思路，采用磷酸化定量蛋白质组学技术分析高温胁迫下坛紫菜磷酸化蛋白质表达水平和磷酸化位点的动态变化，建立磷酸化蛋白差异表达谱；同时围绕应答高温胁迫的信号转导和基因转录调控两个网络的交叉互作调控，将磷酸化蛋白差异表达谱与课题组前期建立的基因差异表达谱进行整合/关联分析和权重基因共表达网络分析，建立坛紫菜高温胁迫应答的信号转导网络，鉴别高温胁迫应答的关键基因；并重点探讨这些关键基因的表达与坛紫菜耐高温的关系，同时结合前期获得的坛紫菜高温胁迫应答的生理学、转录组学和蛋白质组学数据，进一步系统解析坛紫菜高温胁迫应答的分子调控机制，为将来通过分子育种培育坛紫菜耐高温新品种提供理论依据和功能基因。

“高温烂菜”是当前严重阻碍坛紫菜栽培可持续发展的重要因素，每年均给养殖户带来巨额损失，而坛紫菜应答高温胁迫信号转导机制的阐明是全面解析坛紫菜高温胁迫应答机制的关键，有利于进一步指导坛紫菜耐高温品种的选育，对于保证坛紫菜产业的健康发展，具有重要的科学意义和实际应用价值。本研究根据高温胁迫应答的“信号感受—转导—蛋白磷酸化修饰—转录调控—基因差异表达—基因功能分析”的基本过程和研究思路，采用细胞学和分子生物学技术相结合确定了Ca2+信号转导系统在坛紫菜高温胁迫应答过程中的作用；通过磷酸化定量蛋白质组学技术分析了高温胁迫下坛紫菜磷酸化蛋白质表达水平和磷酸化位点的动态变化，建立了磷酸化蛋白差异表达谱；同时围绕高温胁迫应答的信号转导和基因转录调控两个网络的交叉互作调控，将磷酸化蛋白差异表达谱与课题组前期建立的基因差异表达谱进行整合/关联分析和权重基因共表达网络分析，建立了坛紫菜高温胁迫应答的信号转导网络，鉴别并克隆了高温胁迫应答的关键基因；同时结合前期获得的坛紫菜高温胁迫应答的生理学、转录组学和蛋白质组学数据，较为全面系统地解析了坛紫菜高温胁迫应答的分子调控机制；并获得了关键基因6个，发表学术论文10篇（其中SCI论文9篇），授权发明专利3件，获批国审新品种1个。研究结果为通过分子育种培育坛紫菜耐高温新品种提供了理论依据和功能基因。